Final answer:
The Transmission Control Protocol (TCP) is responsible for segmenting messages and managing their segments during the transfer of an HTML document between a web server and a web client. This protocol ensures data integrity and proper order of packets upon arrival.
Step-by-step explanation:
When a user is viewing an HTML document located on a web server, the protocol responsible for segmenting the messages and managing the segments in the conversation between the web server and the web client is the Transmission Control Protocol (TCP). This protocol works hand-in-hand with the Hypertext Transfer Protocol (HTTP) to ensure that data is properly sent and received. TCP breaks down the data into packets, sends them across the internet, and ensures that they are reassembled in the correct order at the destination.
Tim Berners-Lee, while working at CERN, developed the foundational technologies of the web, including HTML, URI, and HTTP. His NeXT computer is famously known as the world's first web server. The web has evolved significantly since its inception at CERN, going through several phases, including the rise and fall of the Netscape Navigator during the 'first browser war'.